For smaller snakes I just use those plastic pot drain things that you stick potted plants on, not sure of their official name. They come in several sizes and are dirt cheap. Just cut a hole in them and you have a cheap usable hide.

For the larger bps, I use litter boxes. You can get the smaller ones made for kittens and they work great!

These all work just as well as the commercial ones, and are a lot cheaper and easy to come by.